Would it be possible for the product of $f ^ $s to contain a "1" and hence pollute your $_ string?

Yes, but no. It could certainly be possible that the XORred string contains a character "1". But this is ok, the tr/\x00/1/c turns anything that is not "\x00" into a "1" anyway - after the tr, the string will only contain "\x00" and "1" characters.

Abigail

In reply to Re: Detecting transpositions by Abigail-II
in thread Detecting transpositions by BrowserUk

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